Ignition switch



July 2', 929- J. A. FORSBERG IGNITION SWITCH Filed April 19, 1926 @4 @Jag @.9

' such as bake ite for example, and a cover 2,.

Patented July 2, 1929.

UNITED STATES JOHN A. FOBSBERG, 0F CHICAGO, ILLINOIS.

IGNITION SWITCH.

Application led April 19, 1926.- ASerial No. 108,018.

My invention relates to ignition controlling means for internal combustion engines.

More specifically, it relates .to means whereby the battery circuit supplying the ignition is automatically openedr when the engine stops, whereby Waste of battery current and consequent deterioration of the storage battery are prevented. i

Other objects and advantages of my invention will be apparent from the present specification and accompanying drawing, wherein Figure 1 represents dia'grammatically a circuit controlling device embodying my -invention;

Figure 2 is a section of Figure 1 on plane 2-2;

Figure 3 is a'detail sectional view of a vacuum-actuated electric contact maker constituting a modified part of the invention; Figure 4 is a diagram showing the electrical circuits used with the device of Figure 1; and

Figure 5 is a diagram showing the elec ltrical circuits used with the device of Figure 3. l

Referring first to Figure 5 of the. drawing,

there is shown a diagrammatic view of an internal combustion engine 24, having the usual distributor 22, and whose ignition is provided by means of the storage battery 20. This battery is kept charged by means of generator 19 driven by the engine, and an automatic cut-out 18 of the usual type is provided, to connect the generator tothe battery when the speed of the engine is suticientbut to disconnect it automatically when said speed falls so low that the battery would discharge back through the generator. The usual key-switch 21 is provided to break the primary ignition circuit through spark coil 25 when the engine is not running. All these detalls are old and well known. My

invent-ion consists in intcrposing in the ignition circuit two devices 13 and 26, which will automatically open the ignition circuit as soon as the engine ceases to operate.v

Referring now to the device 26, which is indicated in ,Figure 5 as comprising a cas-` ing 1 and a cover 2, and which is shown in det-ail in Figure 3, the particular device shown comprises a casing 1 which may bc made of an suitable insulating material made of any suitable material, for instance, a metal. A metallic diaphragm 3 is clamped between the casing 1 and cover 2, which are preferably secured to one another by means of screw threads 8. The dia-- phragm carries a contact element 4. A vent 9 may be provided in the cover 2, as shown. A metallic bushing 5 is secured in the rear wall of casing 1 and is screw-threaded to receive the.l adjusting screw 6, which has a knurled head, as shown, and has a contact 7 at its end, cooperating with contact 4 on the diaphrag1n`3. A tube 1() connects the interior of the casing 1 tothe intake nia-nifold 23 as shown in Figure 5. Wirsill and .tact 17 closed.

The operation of the system is as follows. Upon inserting and operating the proper key in switch 21 in the usualmanner, the ignition circuit will be completed except for the open contacts at 4, 7 and 17. Consequently no current can flow in the ignition circuit until onel or the other of these contacts is closed. However, upon actuating the starting means or the crank, a partial vacuum is at once formed in the manifold 23, and as a result is communicated through tube 10 to the casing 1, whereupon the at-l mospheric pressure will at once push in the diaphragm 3, and therebyclosethe contacts 4, 7. This completes the igmtlon circuit, and upon further cranking of the engine, 1t will start in the usual way. As soon as the engine attains suflicient speed to cause generator- 19 to charge battery 20, the current in 14 will close contact 17 so that now the ignition circuit is completed in two possible ways, namely contacts 4, 7 and 17. If now the throttle be opened very widely, the vacuum in manifold 23 lnay become too poor to retain contacts 4, 7 closed, but at such times the engine is revolving very rapidly, consequently generator 19 is charging battery 2O and holding contact .-17 closed, hence the ignition circuit remains completed even t-hough contacts 4, 7 separate. On the other hand, when the throttle is closed, the

vacuum is .sufficient to hold contacts 4, 7

closed even' though the engine speed drops below that necessary to close contact 17.

v If now, the engine stops, the contact 17 immediately opens, and the contacts 4, 7 will separate also as soon as atmospheric pressure is restored in the casing 1 through tube 10. The result is that the ignition circuit is automatically 'opened immediately after the engine stops. y

While I have described devices 13 and 26. as two separate means, it is evident that they may be combined intoy a single instrument, by fastening an armature corresponding to 15 directly to the diaphragm 3 and placing the electromagnetic windings 14 inside-casing 1 so that either a vacuum inthe said casing 1y or a current in the enclosed Wind- 'f ySuch modification' is in fact the ings 14 will hold contacts 4, 7 together. referred form o f the device, but is describe last for the reason that it is easier. understood after the elements thereof have been described.

Referring now .to Figures 1, 2 andc4, there is shown a vacuum chamber 29 formed as a cylindrical bore in a block of insulating material 30. A diaphragm 31 is held over said chamber 29 by means of vscrews 32! and ring 33, anda protective cover 34 may also be provided if'preferred. A spring 35 is secured to block 30 by means of 4screw 36 and binding post 37.' A stud 38 is secured f to the diaphragm as shown, -and passes through a hole 39 in the spring 35, .the desired adjustment and proper tension being secured by nuts 40. A contact comprising a screw 41 threaded through the/spring 35 `and secured by lock nut 42, cooperates with a fixed contact 51 secured to the block 30 by screw43 and bindin post 44 asvshown.

The device/so. far descrlbed cor-responds in` general structure and function with the de-v vice 26 of Figures 3 and 5. An electromagnet 45. isseated in a bore 46 of the block 30 and the terminals ofits windings are connected to binding osts 47 and 48. An armature 49 is secure to the spring 35 and cooperates with the electromagnet. This corresponds to .the device 13 of Figure 5. A swltch 5 0 pivoted under. screw 36` cooperates with contact stri `51to control the circuit manually. A c eckvalve 52 vcontrols tube 1G.

In operation this devicewill-be connected to the engine 24 as shown in Figure 4. The tube 10 leads to manifold 23 as before, and the 4electromagnet 45 is placed in the circuit between generator 19 and storage battery 20. as before. Upon producing a' vacuum in of the controller, switch 50 may be actuated manually to short-circuit the'contact maker and permit operation of the engine 24 in an emergency.

It will be seen thatif an lautomobile is equipped with my invention, it will be im-` possible to cause the battery to be run down by leaving the ignition key turned on while the engine is at rest even though the distributor breaker contact happens to be closed, yet .the normal starting and operation of the engine are not interfered with.

The check valve 52 is designed to o en when a vacuum exists in the manifold, ut toelose automatically if the engine' backfires, thus preventingl premature release of the diaphragm 31 should such condition arise. The check valve will be of any ordinary commercial type, and will usually be leaky enough to allow atmospheric pressure to berestored in the chamber 29 soon after .the engine stops, and if not, an artificial leak may vbeproduced by slight mutilation of the valve or its seat to cause this desired action.

Having now described a preferred form` of my invention, I claim:'- .i

4 1. An ignition controlling device for internal combustion engines comprising a circuitq closer actuated by and in response to the vacuum in the intake manifold of the engine, said circuit closer including a'block of insulating material having achamber formed therein, a diaphragm closing said chamber, a switch, actuated by said diaphragm, means for adjustably securing the switch to the diaphragm,.a conduit for con'-l necting the chamber to the said intake manifold, and' a check valve in said conduit, said check valve being slightly leaky.

2.`An i nition controlling device for internal com ustion engines comprising a circuitl closer actuated .by and in response to the vacuum in the intake manifold of the1 engine, said circuit closer including a single block of material having therein a bore forming achamber, a diaphragm closing said chamber, a switch actuated by said diaphra m, means for adjustably securing the switc to the diaphragm, a conduit for connecting the chamber to the said intake mani- 'fold, said block having a second bore entirely separate from the first-named'bore, and an .electro-magnetic "relay also controllingy said circuit, an mounted within said second bore. 3. A block of insulating material having two entirely separated bores formed therein, each bein phragm c osing the other end ofone of said closed atone end; a flexible diabores; a conduit communicating with the inphragm; sin-armature carried by said circuit terior of said bore and adapted to be concloser and an electromagnet located in the nected to the intake manifold of an interother bore and cooperating with said arma- 10 nal combustion engine; an electrical circuit ture, to operate the said circuit closer inde- 5 closer mechanically connected to, and operpendently of the diaphragm.

ated by, said diaphragm; means for adjust- In testimony whereof I aix my si ature. ing the circuit closer with respect to the dia- J OHN A. FORSB RG.` 

